Compound engine.



Patented Oct. 7, 1902-.

J. H. WESCOTT.

COMPOUND ENGINE.

(Application filed Jan. 9, 1902.)

{No Model.)

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UNTTED STATES PATENT OFFICE.

JOHN H. XVESCOTT, OF NORFOLK, VIRGINIA.

COMPOUND ENGINE.

SPECIFICATION forming part of Letters Patent No. 710,910, dated October '7, 1902.

Application filed January 9,1902- Serial No. 89,044. (No model.)

To (tZZ whom it may concern:

Beitknown that I, JOHN HJVESCOTT, acitizen of the United States, residing at Norfolk, in the county of Norfolk and State of Virginia, have invented certain new and useful Improvements in Compound Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to engines of the type utilizing high and low pressures, whether sta tionary, portable, marine, or any variety, so long as the cylinders are of different diameters and axially arranged, the pistons being attached to the same rod.

Heretofore it has been common to build up the chest of the high-pressure cylinder to cause it to aline with the chest of the lowpressure cylinder, both valves being attached to the same rod. This has resulted in the use of an unnecessary amount of material, has increased the Weight of the engine without appreciably adding to its strength, and has materially increased the cost of construction and handling.

The purpose of this invention is to materially lessen the cost of manufacture, reduce the weight, and'enable the engine to be constructed at a minimum cost and with. the smallest amount of material possible without detracting from its efficiency and durability.

As previously stated, the improvement is adapted to all types and makes of engines, whether stationary, portable, or marine, employing coaXially-arranged cylinders of different diameters.

For a full description of the invention and the merits thereof and also to acquire a knowledge of the details of construction of the means for effecting the result reference is to be had to the following description and the drawings hereto attached.

lVhile the essential and characteristic features of the invention are susceptible of modification, still the preferred embodiment of the invention is illustrated in the accompanying drawings, in which- Figure 1 is a vertical central longitudinal section of a compound engine, illustrating the application of the invention. Fig. 2 is a section of the oscillating arm and cooperating frame on the line X X of Fig. 1 on a larger scale. Fig. 3 is a section on the line Y Y of Fig. 2. Fig. 1 is a perspective view of the s cillating arm.

Corresponding and like parts are referred to in the following description and indicated in. all the views of the drawings by the same reference characters.

The high-pressure cylinder 1 is in coaxial alinement with the low-pressure cylinder 2 and is connected wit-h the latter by means of a neck portion 3, which is contracted at the end adjacent to the cylinder 1. The enginerod 4 passes through stuffing-boxes in the heads of the cylinder 2 and the inner end'of the cylinder 1 and has the pistons 5 and 6 attached thereto. The cylinder 2 is of greater diameter than the'cylinder 1, and the piston 5 is reciprocated therein by vacuum or. low pressure in the ordinary manner.

The chest 7 of the low-pressure engine is of ordinary construction and receives the valve 8, which controls the ports by means of which the steam is admitted to and exhausted from the cylinder 2. The valve 8 is connected to the stem 9, to which a reciprocating motion is imparted from the eccentric or other convenient portion of the engine in any desired manner. The chest is provided at one side of the high-pressure cylinder 1 and is out of line with the chest 7, being constructed to lie as close to the cylinder 1 as possible consistent with strength and provision for the various steamports. The valve 11, operating within the chest 10, is applied to the stem 12, which latter is connected with the stem 9 in the manner presently to be stated. A bracket 13 projects from the chest 10 and is constructed to form a guide for the projecting end of the stem 9.

The inner ends of the stems 9 and 12 overlap and are connected to an arm 14:, mounted for oscillatory movement, the inner or lower end of said arm being pivotally connected at 15 with the portion 3 of the engine-frame. A link 16 pivotally connects the stem 12 with the arm 14, whereby compensation is had for the relative variation of distance of the pivotal connection between the parts 12 and 14 incident to the arcuate movement of the arm 14 and the rectilinear movement of the stem 12. The oscillating arm 14. has intersecting ICO slots -17 and 18, the slot 17 being at a right angle to the plane of motion of the said arm and the slot 18 being in the plane of motion thereof and receiving the frame 19, located intermediate the ends of the valve-stem 9, so as to reciprocate therewith. A block 20 is slidably mounted with reference to the frame 19 and is shifted by means of set-screw 21, journaled in the ends of the frame 19. Trunnions 22 project laterally from the block 20 in transverse alinement and obtain bearings in blocks 23, slidably mounted in the transverse slot 18, the edges of the bearing-blocks being grooved to embrace the sides of the parts bordering upon the slot 18, so as to hold the bearing-blocks 23 in place and direct them in their movements. The frame 19 may be a part of the valve-stem 9 or attached thereto in any manner and may be of any construction so long as it affords a substantial support for the slide-block 20 in any adjusted position.

From the foregoing it will be observed that the initial motionimparted to the valve-stem 9 is transmitted to the valve-stem 12 through the instrumentality of the oscillating arm 14, frame 19, and the intermediate connections. The pivotal connection of the link 16 with the stem 12 and arm 14 obviates any possible binding of the connections when the engine is in operation. It will also be observed that the chest is located as close to the side of the cylinder 1 as the corresponding part of any direct-acting steam-engine. Hence a minimum amount of material is utilized in the construction of the engine of the type set forth.

The purpose of the set-screw 21 is veryiniportant and constitutes one of the most valuable features of my invention, for the reason that it affords a simple, convenient, and instantaneous means for regulating the lead and cut-off. It is readily seen that by moving the block up or down in the frame 19 and arm 14 the stroke of said arm is shortened or lengthened and the relative longitudinal movement of the stems 9 and 12 thereby regulated.

Having thus described the invention, what is claimed as new is- 1. In an engine of the character set forth and in combination with the chests and valves out of alinement, a pivoted arm mounted for oscillatory movement and having intersecting slots or openings, blocks slidably mounted in one of the said slots, and means pivotally connecting the blocks, respectively, with the said valve-stems, substantially as described.

2. In a compound engine, coaXially-alined high and low pressure cylinders, having offstanding chests constructed as near as possible to their sides, a rod common to both cylinders and bearing-pistons, valves for the respective chests and having their stems projecting and overlapping at their inner ends, an oscillating arm, blocks having slidable connection with the oscillating arm and pivotal connection with the respective valvestems, and means for adjustably connecting the outermost block with the said oscillating arm, substantially as set forth.

3. In an engine, valves having their stems out of line, an oscillating arm having loose connection with one of the valvestems, a frame extended from the other valve-stem, and a block adjustably connecting the frame with the said arm, substantiallyas described.

In testimony whereof I affix my signature in presence of two witnesses.

JOHN H. \VESCOTT. [L. 5.]

\Vitnesses:

J. D. HEARD, A. B. CARNEY. 

